A geometric construction, also called a Verging Construction, which allows the classical Geometric Construction rules to be bent in order to permit sliding of a marked Ruler. Using a Neusis construction, Cube Duplication and angle Trisection are soluble. Conway and Guy (1996) give Neusis constructions for the 7-, 9-, and 13-gons which are based on angle Trisection.
See also Cube Duplication, Geometric Construction, Mascheroni Construction, Ruler, Trisection
Conway, J. H. and Guy, R. K. The Book of Numbers. New York: Springer-Verlag, pp. 194-200, 1996.